"I didn't know any of this before and used to touch them with my bare hands," he said.

James, an Associate Professor at Japan's University of Ryuukyus in tropical Okinawa, said zoanthids were unusual in that biologists didn't know why they contained the poison, palytoxin.

"Some colonies have this poison and some don't. There doesn't seem to be any rhyme or reason why zoanthids in one place are poisonous and the same species in the next bay are not," James said.

Similar to corals and anemones, zoanthids are closely related to both groups but are far less understood.

Zoanthids are a tough group of species found both in deep sea environments and fringe habitats, such as intertidal, back reef and other shallow areas over dead corals. They can be found as individual polyps or as a mat created from small pieces of sediment, sand and rock.

Their ability to incorporate sand into their tissue to help make their structure is a characteristic that sets them apart from soft corals and anemones.

While not much is understood about palytoxin, its use as an anesthetic is being explored, James said.

"These species are everywhere but have been almost entirely ignored in biodiversity studies because no one knows how to identify them," he said.

So far this field trip James has discovered two potentially new zoanthid species, which he will confirm using DNA sequencing when he returns to Japan.

Until then, he is focusing on the biodiversity of zoanthid populations around Heron Island and comparing it with that of Japan.

He is also comparing his research with that of previous CReefs Australia expeditions and hopes to join future expeditions to further his research.